In a substrate processing apparatus that performs vacuum processes such as film formation and etching on a semiconductor wafer (hereinafter, referred to as a “wafer”), a plurality of processing modules are provided in order to enhance productivity. The wafers are processed in each processing module under a vacuum.
A vacuum-side transfer module for transferring a substrate is connected to the plurality of processing modules. A plurality of load lock modules, each configured to switch the internal atmosphere between an atmospheric environment and a vacuum atmosphere, is provided between the vacuum-side transfer module and an atmospheric-side transfer module.
A transfer mechanism equipped with an articulated arm and a sliding mechanism are provided in the vacuum-side transfer module. The transfer mechanism slides in the vacuum-side transfer module using the sliding mechanism and transfers the wafers between the plurality of processing modules and the vacuum-side transfer module and between the vacuum-side transfer module and the load lock modules.
Incidentally, the sliding mechanism is coated with grease. When the wafer is transferred to the processing module by the articulated arm of the transfer mechanism, the grease may enter into the processing module. This may be a cause of contaminating a process chamber. In addition, in a case where the sliding mechanism is provided in the vacuum-side transfer module, the vacuum-side transfer module is increased in size, which increases the footprint of the entire substrate processing apparatus.
On the other hand, in order to transfer the wafers to a plurality of process chambers without having to use the sliding mechanism, the entire length of the articulated arm is required to be lengthened. This increases the size of the vacuum transfer module, thus increasing the footprint of the substrate processing apparatus. It is conceivable to increase the number of arms of the articulated arm and shorten the length of each arm. This complicates the operation of the articulated arm and increases connection locations between the arms and joints. Consequently, there may be a case where a fork cannot pass through a thinly-formed transfer port through which the wafer is transferred, making it impossible to transfer the wafer into the processing module.